Question

我第一次尝试使用Javassist，而且我被卡住了。我在运行时创建类，如果有任何新字段，我想在运行时更改类。我的代码在下面

public static Class generate(String className, Map<String, Class<?>>  properties) throws NotFoundException,
CannotCompileException, ClassNotFoundException {

    ClassPool pool = ClassPool.getDefault();
    CtClass cc=null;
    final ClassLoader contextClassLoader = Thread.currentThread().getContextClassLoader();
    if (contextClassLoader != null)
    {
        pool.insertClassPath(new LoaderClassPath(contextClassLoader));
    }
    try{

        cc = pool.makeClass(className); 
        cc.defrost();
        cc.addInterface(resolveCtClass(Serializable.class));
        for (Entry<String, Class<?>> entry : properties.entrySet()) {
            //add feilds

            // add getter

            // add setter


        }
        cc.addConstructor(generateConstructor(cc,properties,className));
        CtConstructor defaultCons=new CtConstructor(NO_ARGS, cc);
        defaultCons.setBody(";");
        cc.addConstructor(defaultCons);
        return cc.toClass();
    }catch(Exception e){
        cc = pool.get(className);   
        for (Entry<String, Class<?>> entry : properties.entrySet()) {
            try{
                //add feilds
                // add getter

                // add setter

            }catch(Exception e1){
                System.out.println("Fields or method already present");

            }
        }
        try{
            cc.addConstructor(generateConstructor(cc,properties,className));
        }catch(Exception e1){
            System.out.println("Constructor already present");

        }
        try {
            byte[] classFile = cc.toBytecode();
            HotSwapper hs = new HotSwapper(9080);
            hs.reload(className, classFile);
        } catch (IOException | IllegalConnectorArgumentsException e1) {
            // TODO Auto-generated catch block
            e1.printStackTrace();
        }
        return Class.forName(className);


    }

此代码无效。我收到了以下错误

java.lang.ClassNotFoundException：com.sun.jdi.connect.IllegalConnectorArgumentsException

Answer 1

您必须在项目中添加以下依赖项

  <!-- https://mvnrepository.com/artifact/com.sun/tools -->
    <dependency>
        <groupId>com.sun</groupId>
        <artifactId>tools</artifactId>
        <version>1.7.0.13</version>
        <!--<scope>system</scope>-->
    </dependency>

javassist hotswapper获取错误--- java.lang.ClassNotFoundException：com.sun.jdi.connect.IllegalConnectorArgumentsException

1 个答案: